solved

[gilles civario <gilles dot civario at cea dot fr>]

Ok, I solved my problem.
Sorry for the noise.
In the XF86Config file, I've changed the XkbModel from 'pc102' to 'pc105'.
Now, it's working perfecly...
It proofs that questioning others helps to answering itself.

Gilles.
ddxProcessArgument - Initializing default screens
winInitializeDefaultScreens - w 1280 h 1024
winInitializeDefaultScreens - Returning
OsVendorInit - Creating bogus screen 0
_XSERVTransmkdir: Owner of /tmp/.X11-unix should be set to root
(==) Using config file: "/etc/X11/XF86Config"
Markers: (--) probed, (**) from config file, (==) default setting,
         (++) from command line, (!!) notice, (II) informational,
         (WW) warning, (EE) error, (??) unknown.
(WW) No Layout section. Using the first Screen section.
(==) FontPath set to "/usr/X11R6/lib/X11/fonts/misc/,/usr/X11R6/lib/X11/fonts/Speedo/,/usr/X11R6/lib/X11/fonts/Type1/,/usr/X11R6/lib/X11/fonts/CID/,/usr/X11R6/lib/X11/fonts/75dpi/,/usr/X11R6/lib/X11/fonts/100dpi/"
(==) RgbPath set to "/usr/X11R6/lib/X11/rgb"
winDetectSupportedEngines - Windows NT/2000/XP
winDetectSupportedEngines - DirectDraw installed
winDetectSupportedEngines - Allowing PrimaryDD
winDetectSupportedEngines - DirectDraw4 installed
winDetectSupportedEngines - Returning, supported engines 0000001f
InitOutput - g_iNumScreens: 1 iMaxConsecutiveScreen: 1
winSetEngine - Using Shadow DirectDraw NonLocking
winAdjustVideoModeShadowDDNL - Using Windows display depth of 32 bits per pixel
winCreateBoundingWindowWindowed - User w: 1280 h: 1024
winCreateBoundingWindowWindowed - Current w: 1280 h: 1024
winAdjustForAutoHide - Original WorkArea: 0 0 996 1280
winAdjustForAutoHide - Adjusted WorkArea: 0 0 996 1280
winCreateBoundingWindowWindowed - WindowClient w 1280 h 996 r 1280 l 0 b 996 t 0
winCreateBoundingWindowWindowed -  Returning
winCreatePrimarySurfaceShadowDDNL - Creating primary surface
winCreatePrimarySurfaceShadowDDNL - Created primary surface
winCreatePrimarySurfaceShadowDDNL - Attached clipper to primary surface
winAllocateFBShadowDDNL - lPitch: 5120
winAllocateFBShadowDDNL - Created shadow pitch: 5120
winAllocateFBShadowDDNL - Created shadow stride: 1280
winFinishScreenInitFB - Masks: 00ff0000 0000ff00 000000ff
winInitVisualsShadowDDNL - Masks 00ff0000 0000ff00 000000ff BPRGB 8 d 24 bpp 32
winCreateDefColormap - Deferring to fbCreateDefColormap ()
winFinishScreenInitFB - returning
winScreenInit - returning
InitOutput - Returning.
(==) winConfigKeyboard - Layout: "0000040C" 
(**) Using keyboard "RuKeyboard" as primary keyboard
(**) Option "XkbRules" "xfree86"
(**) XKB: rules: "xfree86"
(**) Option "XkbModel" "pc105"
(**) XKB: model: "pc105"
(**) Option "XkbLayout" "fr"
(**) XKB: layout: "fr"
Rules = "xfree86" Model = "pc105" Layout = "fr" Variant = "(null)" Options = "(null)"
winPointerWarpCursor - Discarding first warp: 640 498
winBlockHandler - Releasing pmServerStarted
winBlockHandler - pthread_mutex_unlock () returned

Section "InputDevice"
 Identifier "RuKeyboard"
 Driver     "Keyboard"
 Option "XkbRules"   "xfree86"
 Option "XkbModel"   "pc105"
 Option "XkbLayout"  "fr"
EndSection

Section "Device"
    Identifier  "dummy"
    Driver      "dummy"
EndSection

Section "Monitor"
    Identifier  "dummy"
EndSection

Section "Screen"
    Identifier  "dummy"
    Device      "dummy"
    Monitor     "dummy"
EndSection